Axle shaft disconnect clutch

Abstract

An axle shaft disconnect clutch includes a housing, an axle shaft, a stub shaft, a dog clutch and an inner race. The axle shaft includes a first outer spline and the stub shaft includes a second outer spline. The dog clutch has an inner spline engaged with the second outer spline and the inner race is rotationally fixed and axially displaceable relative to the housing to axially displace the dog clutch and engage or disengage the inner spline with the first outer spline. In some example embodiments, the axle shaft disconnect clutch has a bushing pad fixed to the inner race. The inner race is arranged to push the dog clutch towards the first outer spline to engage the dog clutch, and the inner race is arranged to pull the bushing pad to pull the dog clutch away from the first outer spline to disengage the dog clutch.

What is claimed is: 
     
       1. An axle shaft disconnect clutch, comprising:
 a housing for mounting the axle shaft disconnect clutch to a vehicle; 
 an axle shaft, the axle shaft comprising a first outer spline; 
 a stub shaft, coaxial with the axle shaft, the stub shaft comprising a second outer spline; 
 a dog clutch comprising an inner spline engaged with the second outer spline and a radially extending protrusion; 
 an inner race, rotationally fixed and axially displaceable relative to the housing to axially displace the dog clutch and engage or disengage the inner spline with the first outer spline; and 
 a bushing pad fixed to the inner race, wherein: 
 the inner race is arranged to push the dog clutch towards the first outer spline to engage the dog clutch; 
 the inner race is arranged to pull the bushing pad to pull the dog clutch away from the first outer spline to disengage the dog clutch; 
 the inner race comprises a first arcuate protrusion arranged radially outside of the radially extending protrusion; and 
 the bushing pad is disposed radially inside of the first arcuate protrusion and arranged to contact the radially extending protrusion to pull the dog clutch away from the first outer spline. 
 
     
     
       2. The axle shaft disconnect clutch of  claim 1  wherein the bushing pad is fixed to the first arcuate protrusion with radially extending tabs. 
     
     
       3. The axle shaft disconnect clutch of  claim 1  wherein the bushing pad includes a second arcuate protrusion disposed radially between the radially extending protrusion and the first arcuate protrusion. 
     
     
       4. The axle shaft disconnect clutch of  claim 1  further comprising a stub shaft seal, wherein:
 the housing comprises a cover; and 
 the stub shaft seal is installed in the cover to seal the housing to the stub shaft. 
 
     
     
       5. The axle shaft disconnect clutch of  claim 1  further comprising a first bearing, wherein:
 the housing comprises a cover; and 
 the first bearing is arranged to support the stub shaft on the cover. 
 
     
     
       6. The axle shaft disconnect clutch of  claim 1  further comprising a second bearing arranged to radially align the axle shaft and the stub shaft. 
     
     
       7. The axle shaft disconnect clutch of  claim 1  further comprising a third bearing arranged to support the axle shaft in the housing. 
     
     
       8. The axle shaft disconnect clutch of  claim 1  further comprising a resilient element, wherein the resilient element is arranged to be compressed if the inner race moves towards the dog clutch and the inner spline is not rotationally aligned with the first outer spline. 
     
     
       9. An axle shaft disconnect clutch, comprising:
 a housing for mounting the axle shaft disconnect clutch to a vehicle; 
 an axle shaft, the axle shaft comprising a first outer spline; 
 a stub shaft, coaxial with the axle shaft, the stub shaft comprising a second outer spline; 
 a dog clutch comprising an inner spline engaged with the second outer spline; 
 an inner race, rotationally fixed and axially displaceable relative to the housing to axially displace the dog clutch and engage or disengage the inner spline with the first outer spline; 
 a resilient element; and 
 a washer contacting the dog clutch, wherein: 
 the resilient element is arranged to be compressed if the inner race moves towards the dog clutch and the inner spline is not rotationally aligned with the first outer spline; 
 the resilient element is a wave spring; and 
 the wave spring and the washer are disposed axially between respective annular faces of the inner race and the dog clutch. 
 
     
     
       10. An axle shaft disconnect clutch, comprising:
 a housing for mounting the axle shaft disconnect clutch to a vehicle; 
 an axle shaft, the axle shaft comprising a first outer spline; 
 a stub shaft, coaxial with the axle shaft, the stub shaft comprising a second outer spline; 
 a dog clutch comprising an inner spline engaged with the second outer spline; 
 an inner race, rotationally fixed and axially displaceable relative to the housing to axially displace the dog clutch and engage or disengage the inner spline with the first outer spline; 
 an axially fixed outer race; and 
 a rolling element, wherein:
 the inner race and the outer race comprise respective ramp surfaces; 
 the rolling element is disposed radially between the inner race and the outer race in the respective ramp surfaces; and 
 rotation of the outer race relative to the inner race axially displaces the inner race as the rolling element travels along the respective ramp surfaces. 
 
 
     
     
       11. The axle shaft disconnect clutch of  claim 10  further comprising a ball cage, wherein:
 the rolling element comprises a plurality of balls; and 
 each one of the plurality of balls is disposed in a respective opening of the ball cage. 
 
     
     
       12. The axle shaft disconnect clutch of  claim 10  wherein:
 the housing comprises a cover; 
 the inner race is rotationally fixed on the cover; 
 the housing comprises a first annular wall and the cover comprises a second annular wall; and 
 the first annular wall and the second annular wall restrict axial displacement of the outer race. 
 
     
     
       13. The axle shaft disconnect clutch of  claim 12  wherein:
 the cover comprises a first cylindrical protrusion with axially extending grooves; and 
 the inner race comprises a second cylindrical protrusion with axially extending protrusions disposed in the axially extending grooves to prevent rotation of the inner race relative to the cover. 
 
     
     
       14. The axle shaft disconnect clutch of  claim 10  further comprising an actuator assembly arranged to rotate the outer race, wherein:
 the outer race comprises an outer gear; and 
 the actuator assembly comprises:
 an electric motor; and 
 a first gear engaged with the outer gear. 
 
 
     
     
       15. The axle shaft disconnect clutch of  claim 14  wherein:
 the electric motor comprises a motor shaft; and 
 the actuator assembly comprises a second gear fixed to the motor shaft and engaged with the first gear.